Footwear crampon

ABSTRACT

A crampon including a body extending lengthwise from a rear end to a front end, widthwise between a first side and a second side, and heightwise between a supporting surface and a receiving surface, the crampon including points projecting in the area of the supporting face, as well as a structure for retaining a boot in the area of the receiving surface. The crampon includes a device for adjusting the longitudinal bending strength of the body.

CROSS-REFERENCE TO RELATED APPLICATION

This application is based upon French Patent Application No. 12/01443, filed May 22, 2012, the disclosure of which is hereby incorporated by reference thereto in its entirety, and the priority of which is claimed under 35 U.S.C. §119.

BACKGROUND

1. Field of the Invention

The invention relates to a crampon adapted to be affixed to an article of footwear, such as a boot. Such crampon may be used in disciplines such as mountaineering, walking or climbing on snow or ice, climbing frozen waterfalls, or the like.

2. Background Information

Conventionally, a crampon comprises a body extending lengthwise from a rear end to a front end, widthwise between a first side and a second side, and heightwise between a supporting surface and a receiving surface. In fact, the body is dimensioned so that the receiving surface receives the sole of the boot. The crampon includes points projecting in the area of the supporting surface, in order to be anchored into the ground, or support surface, and thus prevent slipping. The crampon further comprises means for retaining the boot in the area of the receiving surface. These means constitute a binding, that is to say, a system for fastening to the boot as defined in the standard NF EN 893:2011-01. In general, the binding includes one or more members for retaining the boot in the area of the receiving surface.

Crampons are therefore capable of being affixed to various boots to enable a user to move more easily on slippery surfaces, such as glaciers, snowfields, frozen waterfalls, or any snow-covered or icy terrain. Nevertheless, each type of crampon is more suited to a particular terrain configuration, or to a style of practice, than another.

Certain crampons promote walking on level or slightly inclined terrain. Such crampons have sufficient flexibility to accompany the flexural deformations of the sole assembly of the boot during foot rolling movements. In other words, the crampon is capable of flexing longitudinally along a transverse axis during walking. Due to this feature, the user feels less fatigue when walking. As a corollary, however, a disadvantage of a flexible crampon is user fatigue in highly inclined or vertical passages, such as may be encountered on a glacier or an ice wall. Indeed, the flexibility of the crampon requires the user to apply significant forces to control and maintain support on steep slopes or in the walls, as, in this case, the grip on the ground occurs mainly through the front points, which requires a substantial strain on the calves. In addition to fatigue in highly inclined or vertical passages, the accuracy of the front support, although correct, is not optimal.

Also notable are other crampons, which promote walking on very inclined or vertical terrain. These crampons have sufficient rigidity along their length so that the forces and impulses related to a grip on the ground or on an ice wall, in the area of the front points, are transmitted to the foot throughout the entire sole assembly of the boot. This mode of transmission reduces user fatigue, as the user experiences a less substantial bias on his/her calves to control and maintain support. The support forces applied are also more accurate, compared to a flexible crampon, because the entire sole assembly is involved in the control. As a corollary, however, a disadvantage of a rigid crampon is user fatigue in horizontal or slightly inclined passages, such as found on glaciers or on domes. Indeed, the rigidity of the crampon strongly opposes, or even prevents, longitudinal bending of the sole assembly and good foot rolling movement during walking.

To summarize the state of the art, it can be said that certain crampons are more suitable for horizontal or slightly sloping terrain, while others are more suitable for very inclined or vertical terrain, such as ice walls.

SUMMARY

In view of the foregoing, the invention generally improves a crampon adapted to be affixed to a boot. More specifically, the invention seeks to ensure that the crampon is suitable for all situations and all styles of practice, whether on horizontal, slightly inclined, steeply inclined, or vertical terrains. In other words, the invention is directed to a crampon that has greater versatility.

To his end, the invention provides a crampon comprising a body extending lengthwise from a rear end to a front end, widthwise between a first side and a second side, and heightwise between a supporting surface and a receiving surface, the crampon comprising points projecting in the area of the supporting surface, as well as a mechanism to retain a boot in the area of the receiving surface.

The crampon according to the invention comprises a device for adjusting the longitudinal bending strength of the body.

This means that it is possible to increase or reduce the rigidity associated with longitudinal flexure. It could also be said that the longitudinal bending flexibility of the body can be increased or decreased. This modifies the extent of the active surface of the crampon body, in the sense that a force applied to a point is transmitted locally to the sole assembly of a boot if the body has low rigidity, and in the sense that a force applied to a point is transmitted to a large surface of the sole assembly if the body has a higher rigidity. In the first case, the sole assembly can follow the rolling movement of the foot when walking on level or slightly inclined terrain, which makes is possible to walk comfortably. In the second case, front supports or impulses on steeply inclined or vertical terrain are transmitted to a large portion, if not the entirety, of the sole assembly and of the foot, thereby increasing the accuracy of these supports and impulses. In both cases, user fatigue is reduced.

In general, the crampon of the invention is more versatile, in terms of its cooperation with the ground, compared to a crampon according to the prior art.

The invention provides an improved crampon adapted to be affixed to a boot.

BRIEF DESCRIPTION OF DRAWINGS

Other features and advantages of the invention will be better understood from the description which follows, with reference to the annexed drawings illustrating, by way of a non-limiting embodiment, how the invention can be embodied, and in which:

FIG. 1 is a front perspective view of a crampon according to an embodiment of the invention;

FIG. 2 is a side view of the crampon of FIG. 1, including a boot;

FIG. 3 is a cross section along the line III-III of FIG. 2, in a case in which the longitudinal bending rigidity of the crampon body is maximum;

FIG. 4 is similar to FIG. 3, in a case in which the longitudinal bending rigidity of the crampon body is minimum;

FIG. 5 is a side view of the crampon of FIG. 1, alone, in a case in which the rigidity of body is maximum;

FIG. 6 is similar to FIG. 5, in a case in which the rigidity of the body is minimum and the crampon is used on level terrain;

FIG. 7 is similar to FIG. 5, in a case in which the rigidity of the body is minimum and the crampon is used on substantially inclined terrain.

DETAILED DESCRIPTION

The embodiment described below with reference to FIGS. 1-7 relates to crampons for mountaineering, walking on snow or ice, and for climbing a frozen waterfall. However, the invention is applicable to other disciplines in which the use of such crampons is required or convenient.

As shown in FIG. 1, a crampon 1 provided to receive a boot 2, as will be described further below, includes a body 3 extending lengthwise from a rear end 4 to a front end 5, widthwise between a first edge 6 and a second edge 7, and heightwise between a supporting surface 8 and a receiving surface 9. The supporting surface 8 is structured and arranged to be positioned facing the ground, whereas the receiving surface 9 is structured and arranged to receive the sole assembly of the boot 2.

In a non-limiting fashion, the length of the clamp 1 is adjustable to adapt to boots of various sizes, that is to say, of various lengths. To this end, the body 3 comprises a rear plate 10 and a front plate 11, as well as a bridge 12 connecting the rear 10 and front 11 plates to one another. As shown in FIG. 2, for example, a first linkage 13 connects the rear plate 10 and the bridge 12 to one another, and a second linkage 14 connects the front plate 11 and the bridge 12 to one another. The first linkage 13 comprises a nut 15 affixed to the rear plate 10, as well as a screw 16 affixed to the bridge 12, for example. Similarly, the second linkage 14 comprises a nut 17 affixed to the front plate 11, as well as a screw 18 affixed to the bridge 12, for example. The linkages 13, 14 are used to ensure that the three constituent parts of the body, namely the rear plate 10, the bridge 12, and the front plate 11 are kept together. The linkages are also used to adjust the length of the body 3 and, consequently, the length of the crampon 1. To achieve this, it suffices to turn a screw relative to a nut.

The crampon includes points 20 projecting in the area the supporting surface 8. More specifically, the rear plate 10 carries points 20, for example three, oriented substantially perpendicular to the supporting surface. Similarly, the front plate 11 carriers points 20, for example five, four of which are oriented substantially perpendicular to the supporting surface 8, and one of which is oriented obliquely and forward, in the extension of the front plate 11. While all of the points 20 enable a grip into the snow or ice, on a level or fairly slightly inclined terrain, the forward-oriented point enables a grip into a vertical or steeply inclined wall. Ultimately, the crampon 1 is very versatile in terms of its grip. However, other structural arrangements can be provided.

The crampon 1 also includes structure 21, 22 for retaining the boot 2 in the area of the receiving surface 9. For example, and without limitation, the crampon 1 comprises a first member 21 for retaining the boot 2 in the area of the rear end 4. This member 21 is made in the form of a hook. The crampon 1 further comprises a second member 22 for retaining the boot 2 in the area of the front end 5. This member is made in the form of a stirrup. Each member 21, 22 is provided here to cooperate by hooking with, or otherwise engaging, the boot 2. More specifically, the boot 2 includes a sole assembly 23 and an upper 24. The sole assembly 23 projects from the upper 24 at the front and rear of the boot. The crampon attachment, that is to say, its positioning on the boot, is therefore carried out by inserting the front projection into the stirrup 22, and then by lowering the heel so that the rear projection passes below the hook 21. Conversely, the crampon detachment is carried out by moving the hook 21 away from the boot, and then by moving the boot away from the crampon. Although the retaining structure described above is satisfactory, other retaining structures may be provided.

According to the invention, the crampon 1 comprises a device 31 for adjusting the longitudinal bending strength of the body 3. The operation of the adjustment device 31 is described in greater detail below, but it should be noted here that the adjustment device 31 enables the body 3 to be more or less rigid in longitudinal bending, in relation to a transverse axis. As a corollary, it can also be said that the adjustment device 31 enables the body 3 to be more or less flexible in longitudinal bending, or to vary its state between a level of flexibility and a level of rigidity. This concept is subjective, in part because it depends upon the weight and the level of experience of the user. In any case, a high rigidity of the body 3 promotes the grip on steeply inclined or vertical terrain, and less rigidity promotes walking on slightly inclined or level terrain. Ultimately, the crampon according to the invention is versatile, because it optimizes the conditions of use for all types of terrain.

According to the embodiment proposed, and in a non-limiting fashion, the body 3 comprises the rear plate 10 and the front plate 11, and the device 31 for adjusting the longitudinal bending strength is arranged between the plates 10, 11. This enables a central region of the body 3 to bend or, conversely, to stiffen. Thus, when adjusted to be relatively flexible, the body 3 promotes good foot rolling movement, i.e., such as bending of the foot and boot about the metatarsophalangeal joint and area corresponding thereto, respectively. This reduces user fatigue on flat terrain.

As can be understood with reference to all FIGS. 1-7, the adjustment device 31 comprises at least one blade 32, 33 extending between the rear 10 and front 11 plates, each blade 32, 33 being rotatably mounted in relation to the plates 10, 11 along a longitudinal axis L of the body 3. The blades are parallel to one another when there are more than one. The blades 32, 33 are made from any suitable material, such as steel or any equivalent metal, a composite material, or the like. In each case, a blade is flexible in longitudinal bending along a transverse axis parallel to its thickness. Conversely, the blade is rigid in longitudinal bending along a transverse axis perpendicular to its thickness. Therefore, as explained below, the previously mentioned orientation of the blades directly affects the bending rigidity of the body 3 of the crampon 1.

According to the illustrated embodiment, but not limiting, the adjustment device 31 includes two blades 32, 33 parallel to each other, as well as a rear bridge 40 and a front bridge 41 connecting the blades 32, 33 to one each other, the rear bridge 40 being connected to the rear plate 10, the front bridge 41 being connected to the front plate 11. More specifically, the screw 16 of the first linkage 13 engages the rear bridge 40 to affix the latter to the rear plate 10. Similarly, the screw 18 of the second linkage 14 engages the front bridge 41 to affix the latter to the front plate 11. The bridge 12, which makes the connection between the rear 10 and front 11 plates, is formed by the blades 32, 33 and the rear 40 and front 41 bridges of the adjustment device 31. In fact the latter fulfills two functions, including the function to join the rear 10 and front 11 plates, as well as the function to adjust the bending rigidity of the body 3.

In practice, as can be understood from FIGS. 3 and 4, the blades 32, 33 can be oriented parallel to the receiving surface 9 or, alternatively, the blades 32, 33 can be oriented perpendicular to the receiving surface.

If the blades 32, 33 are perpendicular to the receiving surface 9, as shown in FIGS. 3 and 5, the body 3 has a maximum longitudinal bending rigidity along a transverse axis parallel to the receiving surface 9. Indeed, in this case, the mechanical inertia of the blades is maximum for the aforementioned bending. Consequently, the crampon 1 retains its shape, thereby making it very effective on very inclined or vertical terrain.

Conversely, if the blades 32, 33 are parallel to the receiving surface 9, as shown in FIGS. 4, 6 and 7, the body 3 has a minimum longitudinal bending rigidity along a transverse axis parallel to the receiving surface 9. Indeed, in this case, the mechanical inertia of the blades is minimum for the bending considered above. Therefore, the crampon 1 can bend in order to switch alternatively from the straight configuration of FIG. 6 to the curved configuration of FIG. 7, thus enabling it to follow the deformations of the sole assembly related to the foot rolling movement. In this case, the crampon is very effective in slightly inclined or level terrain.

The transition from a rigid position to a more flexible position of the body 3, which corresponds to a change in the blade orientation, as has just been described and shown, is carried out by a simple manipulation, or manual operation, when the crampon is separated from the boot. It suffices to rotate the blades 32, 33, that is to say, the bridge 12 in this case, along the longitudinal axis L. The mode for adjusting the rigidity of the body 3 is discontinuous, in the sense that it provides two clearly distinct and differentiated positions for which there is a substantial difference in rigidity or flexibility, for the two positions of the blades, and that these two positions are clearly differentiated: they correspond to an angular offset of 90°.

Still according to the embodiment illustrated and being described, when the blades 32, 33 are parallel to the receiving surface 9, one of these blades is flush with the receiving surface. This enables the sole assembly 23 of the boot 2 to keep the blades in their position during use of the crampon.

Similarly, when the blades 32, 33 are perpendicular to the receiving surface 9, a side of one or more of the blades is flush with the receiving surface 9. This also enables the sole assembly 23 to maintain the blades in their position during use of the crampon.

The rear bridge 40, which connects the blades to one another, is itself connected to the rear plate 10 by a screw-nut connection 13, the same one that connects the bridge 12 to the rear plate 10. Similarly, the front bridge 41, which also connects the blades 32, 33 to one another, is itself connected to the front plate 11 by a screw-nut connection 14, the same one that connects the bridge 12 to the front plate 11. It has been shown that due to this arrangement, the bridge 12 and the adjustment device 31 are one and the same element.

Further, an elastic mechanism 42 is arranged between the plates 10, 11. The elastic mechanism 42 shown in this embodiment is a spring acting between the rear bridge 40 and the screw 16 of the screw-nut connection 13, which itself acts between the rear plate 10 and the bridge 12. More precisely, the spring 42 pushes the screw toward the front end 5, thereby enabling the body 3 to reversibly elongate elastically during crampon attachment. The spring 42 is located between the blades 32, 33, thus making the structure of the bridge 12 compact.

In any case, the invention is made from materials and according to implementation techniques known to one with ordinary skill in the art.

The invention is not limited to the particular embodiments described above and shown in the drawing, and includes all technical equivalents that fall within the scope of the claims that follow.

In particular, the transition from a high rigidity state to a lower rigidity state, by the device for adjusting the longitudinal bending strength of the body 3, can be provided to take place continuously. In this case, the mode for adjusting the rigidity of the body 3 is continuous.

A bending strength adjustment device comprising a transverse hinge axis, combined with a locking device, can also be provided. In this case, the latter may or may not selectively allow the articulation of two plates connected to one another.

At least because the invention is disclosed herein in a manner that enables one to make and use it, by virtue of the disclosure of particular exemplary embodiments of the invention, the invention can be practiced in the absence of any additional element or additional structure that is not specifically disclosed herein. 

1. A crampon comprising: a body extending lengthwise from a rear end to a front end, widthwise between a first edge and a second edge, and heightwise between a supporting surface and a receiving surface; points projecting in the area of the supporting surface; a retaining device for retaining a boot in an area of the receiving surface; an adjustment device for adjusting the longitudinal bending strength of the body.
 2. A crampon according to claim 1, wherein: the body comprises a rear plate and a front plate; and the adjustment device is arranged between the plates.
 3. A crampon according to claim 2, wherein: the device for retaining a boot comprises: a first member structured and arranged to retain the boot in the area of the rear end; a second member structured and arranged to retain the boot in the area of the front end; and an elastic mechanism arranged between the plates.
 4. A crampon according to claim 2, wherein: the adjustment device comprises at least one blade extending between the front and rear plates; each of the at least one blade is rotatably mounted in relation to the front and rear plates along a longitudinal axis of the body.
 5. A crampon according to claim 4, wherein: the adjustment device comprises: two blades parallel to one another; and a rear bridge and a front bridge connecting the blades to one another, the rear bridge being connected to the rear plate, the front bridge being connected to the front plate.
 6. A crampon according to claim 4, wherein: the blades are structured and arranged to be oriented parallel to the receiving surface; and the blades are structured and arranged to be oriented perpendicularly to the receiving surface.
 7. A crampon according to claim 4, wherein: when the blades are parallel to the receiving surface, one of these blades is flush with the receiving surface.
 8. A crampon according to claim 4, wherein: when the blades are perpendicular to the receiving surface, a side of one or more of the blades is flush with the receiving surface.
 9. A crampon according to claim 5, wherein: the rear bridge is connected to the rear plate by a screw-nut connection; and the front bridge is connected to the front plate by a screw-nut connection.
 10. A crampon according to claim 9, wherein: the elastic mechanism is a spring acting between the rear bridge and the screw of the screw-nut connection. 